Liquid-feed system.



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UQUID FEED SYSTEM. APPLICATION FILED 0019,1916.

Patentefi June 19, 1917 2 SHEETS-SHEET I.

C. L. STOKES uoum FEED SYSTEM.

APPLICATIO N FILED OCT-M1916 1,230,537. Patented J une 19, 19172'SHEETSSHEET 2.

M I/WE/WOW Ora/WA 528m",

. f unirn enemies L. s'roKns, or Los ANsnLn s, cALIroisn'IA.

manic-F ED SYSTEM.

Specification of Letters Patent. Patgnted June 1%,19176 Applicationfiled October 9, 1916. Serial No. 124,473.

To all whom it may concern:

Be it known that I, CHARLES L, STOKES,

a citizen of the United States, residing at Los Angeles, in the countyof Los Angeles,

State of California, have in\ entednew and useful Improvements inLiquid-Feed Sysii terns, o'f'whieh the following is a specifica- Itosystems for feeding liquid fuel for in tion. i i

This invention relates to systems for feed.

. their relations and connections; 1g. 2 is an enlarged detail sectionof the COHILQCtlOIl to ing or lifting liquids,,an d,- in its more pariicular. phase hereinafter described, relates teraal coinhustionenginesof any type.

It isan object of this invention toprovide a .shnplified means forlifting liquid by the operation of suctionyand particularly-theoperation of suct on from an' internal cornbusti'on-engine to lifthquid.fuel to a carbureter for the engine. It is an object of this inventionto provide a form of means which frnay be readily combined with acarbureter;

that is, which may be constructed as a unit with the carburetor, withthe object of simplii'ying the combined construction.

In my co-pending applications .8. Nos. 91,303 and120,069 filed April 15,1916, and

Sept ltth; 19 16 ,'1 espectively, I'have erev I plained'and laid claimsgenerally to mechanism for liftingliquidiuel from a low level tank to ahigh level service reservoir or to feed the carburetcr, embodyingadmission of air to the liquid lifting line and to the fuel liftingline.

In such liquid feed systems as herein de; scribed, the liquid (the fuel)is lifted by ,"suction to a reservoir thesuetion being appliedintermittently andatmospherlc pressure being .admittedfto the surface ofthe liquid in the reservoir during the periods be .tween theapplications of suction so that the liquid in the reservoir may feed by.gravity into the carbureter, the chamber of which is in communicationwith the atmosphere. It

.is an object of this invention to provide simplified means tor cuttingof? the application of suction and for admitting atmosphcric pressure tothe liquid in the reservmr; and it is also an ob ect,. i'n connectionherewith, to provide suclr means in such shown indetail in Fig. 3..

'hole 27 may. be lowered form as to increase the lifting eiiiciency ofthe device.

Thev foregoing are among thGYObJGOlZS of this invention; but others willappear-from ,the following description of preferred forms.

of my invention and the illustrations there of in the accompanyingdrawings, in which; Figure l is a diagram showing the various opcratveparts ofiny system and showing the main vfuel tank; Fig, 3'is. anenlarged detail section showing the means of admitfed by the liquid fromthe tank; This tank has. the usual filling plug at 12 with an air inletto apply atmospheric pressure to the liquid in the tank. The liftingpipe13 connects with the bottom of the tank asshown.

The lifting pipe connects into a fitting 14 i which has a. liquid.passage 15 communicet-- mg with the tank, and has also an air nozzle 16controlled by a needle valve 17 to admit air into liquid flowing fromthe tank into pipe 13. The air is drawn through the pipe 18, whose upperend is above the liquid level in tank 10. The amount of air admitted atnozzle 16 may be regulated or coinpletely shut oh by. 'alve 17 1 At a.pointintermediate in height between the tank 10f and the servicereservoir 25, I connect anair pipe 26 with the pipe 13; theconnectionheing through a very small In practice, for the amount of fuellifted for an ordinary automobile, this drill hole 27 is of about thesize of a. No. 60 drill. The stand pipe26 is solely for the purposeofpreventing the escape of fuel in the event of going down a. steep gradeor in other conditionswhere the below the level of the fuel in the tank10.

The pipe 13 leads .to the top of the service.

reservoir 25 and discharges into thatreservoir through the cover-30 andthrough a.

drill 11019127, as

nipple or baffle 31 extending into the reservoir beneath the cover; thisbaflie being for the purpose'of preventing the mixed air and liquidbeing drawn immediately to the suction port 32 before the air and liquidcan separate. The suction pipe 33 extends from the intake manifold 34 ofthe engine (at -(as compared with the weight of ordinary floats of thischaracter) so that its weight is sufficient to pull the valve 36 downagainst the suction tending to keep it up, when the liquid level inreservoir 25 has fallen so that the liquid support of the float ispartially withdrawn. From the lower part of reservoir 25 the liquid fuelpasses out through pipe 40 to the carbnreter 11, passing the up Wardlyclosing valve 41. provided for the purpose of keeping the fuel in thecarbureter from being sucked back into the reservoir 25 when suction isapplied to the reser voir. The valve 41 may be placed at the carbureterand seated by gravity, as shown in Fig. 6.

I now explain the action of the system! said action being the same forboth forms of system illustrated, with the exceptions hereinafter noted.

When the service reservoir is full of liquid the float 40 moves up tothe position shown and moves the valve 36 to close suction port 32. Theclosure of this suction port prevents further application of suction tothe reservoir. Gradual flow of liquid out of the reservoir to thecarbureter lowers the liquid level in the reservoir and takes away theliquid support of float 40. When the liquid level has fallen to such anextent that the unsupported weightof the float is suflicient to overcomethe suction tending to support valve 36, then the float will fall,carrying valve 36 with it and suction will be reapplied to the upperpart of the reservoir. in an actual apparatus the arrangement is madesuch that the liquid level in the reservoir only falls through a smalldistance before the valve 36 is moved downwardly.

Suction being applied to'the reservoir, is of course, also applied topipe 13. The liquid from tank IO normally stands up in pipe 13 to aheight depending upon the amount of liquid in the tank; but the air port27 is always highcn than the normal liquid level. Suction applied topipe 13 will imnu-diatcly begin to draw air into the port 27: but theamount of air introduced through this port is insuiiicient to break thesuction. I'he fuel therefore begins tori-so in pipe 13v and, afterpassing port 27, this fuel is intermingled with the air drawn throughthe port. The valve 17, at the lower end of pipe 13, may be regulated toalso admit a restricted quantity of air, or v then drawn up through thep1pe'13 and over into the reservoir 25, where thelliquid and .airseparate, the air being drawn into the engine manifold and the liquidsettlin into the body of liquid in the reservoir. s the liquid level inthe reservoir rises, the float 4O iimovedupwardly until the valve 36 isagain seated. cutting off the application of suction. Immediately theapplication of suctionis cutoff, the column of mixed liquid and air inpipe 13 is arrested in motion and the liquid settles back through thepipe to its normal level. By this action the port 27 is again uncoveredand communication with atmosphere is restored to the reservoir 25)through the pics 13 and 26.

It will now e seen that the air port 27,

' located at a point'above the normal level of liquid, performs twofunctions; one to admit atmospheric pressure to the liquid in theservice reservoir when suction is not being applied and when theatmospheric pressure is needed to allow the liquid in the servicereservoir to flow out; and the other being to supply air to the risingcolumn of liquid in pipe 13 to facilitate the upward movement of thecolumn. So far as either function of port 27 is concerned. it 1s more orlessg immaterial whether air is admitted at thelower end of pipe 13;although the admission of some air at the lower end of the pipefacilitates somewhat the raising of the mixed column of air and liquid.The point, at which port 27 enters the communication depends more orless on the vertical distance through which the liquid is lifted. If thelift is short the port may he very close to the service reservoir; infact it may be at the service reservoir itself.

With the arrangement as described. it will-be seen that the servicereservoir is always open-restr1etedly open-to atmosphere, at all times,The atmospheric port need not at any ti 'The operation of the systemshown in Figs. 5 and 6 is essentially the same as that.

just described. In these figures lshow the service reservoir 25*constructed in a unit with the carbureter 11. The service reservoir hasthe same float operating the valve 36 through the medium of the lever 37connected at 39 with the float. The suction pipe 33 connects in the samemanner as before described with the intake manifold 34 of the engineabove the throttle valve 35"; The carbureter itself may be of any of theusual constructions; embodying, for instance, theliquid nozzlecontrolled oby needle valve '51 and located in the, air passage 52 whichconnects directly with the intake manifold.

of the engine. Liquid fuel is supplied to the nozzle 50 from the fuelchamber 53, which is in communication at 54 with atmosphere.

But this chamber has no float or valve as is ordinarily the case. Ahorizontal liquid pas-- sage 55 may connect the bottom of reservoir .25?vvith'the bottom of chamber 53;.and any suitable check valve, indicatedat 56, may be placed in this communication to prevent back flow ofliquid from chamber 53 tdreseruoir :25 when suction is applied to thereservoir. Whenevertheliquid level in reservoir 25 is higher than thatin chamber 53, liquid w ill fl'ova from the, reservoir to the chamber toreplenish the supply in the chamher. The maximum height of liquid inchamber 53 is level with "the maximum height in resenvoir 25 and thismaximum height is controlled entirely by the ziction of float 40 and,valve 36; becausewhenever the valve. 36 is closed, itis impossibletointroduce liquid into the reservoir by the suctibn action.

i In this last egfplainedform of systein, it"

willbe seen that the float dQ iot only acts to maintain the level of,liquid in the'chamber 25 but also acts to maintain the level of liquidin chamber 53 and tolimit the rise of liquid in that chamber.Consequently, the" float 40' performs a double function in that itcontrols the application of suction to the servicereservoir andcontrolsthe lifting of liquid from tank 10' and the filling of thereservoir, and also controls the liquid level in the chamber 53 whichdirectly and immeQ diately feeds the carburetor proper, particularly incase where the level ofthe carbureter may be below that of the fuelintank 10. Having described a preferred form of my invention, I claim:

1. In a liquid feed system for an internal -,coihbust.ion engine, thecombination'of a liquid tank, aliquid reservoir above said tank,communication between the tank and the reservoir, means for admittingatmos phere to said communication above the normal. liquid level thereinand below the normal liquid level in the reservoir, means for applyingsuction to the upperpait ofthe v v and to draw therefrom volr, a'communicationpipe leading from the fuel tank to the upper part of the.reservoir,

means to restrictedly introduce"atmosphere 4 to. the communication pipeat a point to en.- .telr the column" of liquidmoving-upwardlythereinmeans to apply suction to the upper part of the reservoir, afloat and a valveoperated by the float to cut off suction from thereservoir when the liquid level. in the reservoir reaches apredetermined point.

3. In combination with a carburetor having a fuel chamber open toatmosphere, a

low level liquid fuel tank and a high level service reservoir feedingthe carbureter chamber by gravity, communication between the'tank andreservoir, means to intermittently apply suction to the reservoir, andmeans to restrictedly admitatmos'phere to said communication atra pointabove the normal level of liquid therein and at apoint to enterthecolumn ofliquid movingupwardly therethrough. I

ing a fuel chamber open to atmosphere, a

low level liquid fuel, tank and a high level service a reservoir feedingthe carbureter chamber by gravity, communication between the tank andreservoir, means to controllably-apply suction to the reservoir, andmeans to restrietedly admit atmosphere to said communication at a pointabove the normal level of liquid therein andat a'point 4. In combinationwith a carburetor hav to enter the column .of' liquid moving-upwardlytherethrough;

5. In combination with a carbureter, a lowlevel liquid fuel tank,' aliquid fuel reser voir above the carbur'eter and imcommuni cation Withit to supply it with fuel, com-1 municatidn, between the tank and thereser- .voir, means for restrictedly admitting atmosphere to saidcommunication above the normal liquid level therein and at a point wherethe admitted atmosphere enters the upwardly moving column of liquidmoving from the tank to the reservoir, and commu nication-means tointermittently apply to the upper part of the reservoir the same suctionthat is appliedto the carbureter to maintain a partial vacuum in thereservoir w the air which enters it with the fuel.

reservoir to discontinue the.

6. Incombination with a carbureter, alow level liquid fuel tank, aliquid fuel reservoir above the carbureter and in communication with itto supply it with fuel, communication between the tank and the.reservoir, means for restrictedly admitting atmosphere to saidcomnuinication above the normal liquid level therein and it a pointwhere the admitted atmosphere enters the lip- 7. In combination with acarburetor having a li uid fuel chamber open to atmosphere. a

'bureter chamber by gravity, communication between the tank andreservoir. means to restrictedly admit atmosphere to said commu nieationat a point above thenormal liquid level therein and below the normalliquid level'in the reservoir, and llltlllS to intermittently apply tothe upper part of the reservoir thesame suction that is applied to thecarbureter to maintain apartial vacuum in the reservoir to drawtherefrom the air which enters the reservoir with the liquid iuel.

S. In combination with a carburetor having a liquid fuel chamber opentoatmospherc. a low level liquid'fuel tank and a high level servicereservoir feeding the carburetcr chamber by gravity, communicationbetween the tank and reservoir, means to restrictedly admit atmosphereto said communication at a point above the normal liquid level in thereservoir, means to apply to the upper part of the reservoir the samesuction that applied to the carburetor to maintain low level liquid fueltank and a high level service reservoir feeding the cara partial vacuumin the reservoir and to draw therefrom the air which enters therese'rvoir with the liquid fuel, and valve means controlled by the levelof liquid in the reservoir to discontinue the application of suctionthereto,

9. In combination with a carbureter having a liquid fuel chamber open toatmosphere, a low level liquid fuel tank and a high level servicereservoir feeding the carbureter chamber by gravity, communicationbetween the tank and reservoir, means to restrictedly admit atmosphereto said comn'lunication at a point above the normal liquid level therein and below the normal liquid leveltin the ,reservoir. means to applysuction to the upper part of the reservoir. and valve means co'ntrolliimthe. application of such suction embodying a valve and float means toclose the valve when the liquid reaches a predetermined high level andto open the valve when the liquid reaches a predetermim-d low level.said levels being separated by a predetermined distance.

10. In a liquid feed system for an internal combustion engine. thecombination of a liquid tank, a liquid reservoir above. said tank,communication between the. tank and, the

reservoir, means for admitting atmosphere to said communication abovethe normal liquid level therein andbelow the normal liquid level in thereservoir. said means including an air supply passage extending upwardand connnunicating with the atmosphere at a point above the maximumlevel of the liquid in said reservoir, means or applying suction to theupper part of the rcservoir, said means carrying the admitted atmosphereto mix with the carbureted charge of the engine, and float-actuatedvalve means for cutting oli' suction to the reservoir.

In witness that I claim the foregoing I have hereunto subscribed my namethis 30th day of September, 1916.

CHARLES L. STOKES.

